NEW YORK (AP) — Two major airports reopened and the floor of the New York Stock Exchange came back to life Wednesday, while across the river in New Jersey, National Guardsmen rushed to rescue flood victims and fires still raged two days after Superstorm Sandy.

For the first time since the storm battered the Northeast, killing at least 59 people and doing billions of dollars in damage, brilliant sunshine washed over the nation's largest city — a striking sight after days of gray skies, rain and wind.

At the stock exchange, running on generator power, Mayor Michael Bloomberg gave a thumbs-up and rang the opening bell to whoops from traders on the floor. Trading resumed after the first two-day weather shutdown since the Blizzard of 1888.

Kennedy and Newark Liberty airports reopened with limited service just after 7 a.m. New York's LaGuardia Airport, which suffered far worse damage and where water covered parts of runways, remained closed.

It was clear that restoring the region to its ordinarily frenetic pace could take days — and that rebuilding the hardest-hit communities and the transportation networks that link them together could take considerably longer.

About 6.5 million homes and businesses were still without power, including 4 million in New York and New Jersey. Electricity was out as far west as Wisconsin and as far south as the Carolinas.

The scale of the challenge could be seen across the Hudson River in New Jersey, where National Guard troops arrived in the heavily flooded city of Hoboken to help evacuate thousands still stuck in their homes and deliver ready-to-eat meals. Live wires dangled in floodwaters that Mayor Dawn Zimmer said were rapidly mixing with sewage.

Thousands of people were still holed up in their brownstones, condos, and other homes in the mile-square city is across the Hudson River from New York.

And new problems arose when firefighters were unable to reach blazes rekindled by natural gas leaks in the heavily hit shore town of Mantoloking. More than a dozen homes were destroyed.

President Barack Obama planned to visit Atlantic City, N.J., which was directly in the storm's path Monday night and where part of the historic boardwalk washed away.

Gov. Chris Christie said he plans to ask the president to assign the Army Corps of Engineers to work on how to rebuild beaches and find "the best way to rebuild the beach to protect these towns."

Outages in the state's two largest cities, Newark and Jersey City, left traffic signals dark, resulting in fender-benders at intersections where police were not directing traffic. At one Jersey City supermarket, there were long lines to get bread and use an electrical outlet to charge cellphones.

Amid the despair, talk of recovery was already beginning.

"It's heartbreaking after being here 37 years," Barry Prezioso of Point Pleasant, N.J., said as he returned to his house in the beachfront community to survey the damage. "You see your home demolished like this, it's tough. But nobody got hurt and the upstairs is still livable, so we can still live upstairs and clean this out. I'm sure there's people that had worse. I feel kind of lucky."

As New York began its second day after the megastorm, morning rush-hour traffic was heavy as people started returning to work. There was even a sign of normalcy: commuters waiting at bus stops. School was out for a third day.

The Brooklyn-Battery Tunnel, connecting Brooklyn to Manhattan, and the Holland Tunnel, between New York and New Jersey, remained closed. But bridges into the city were open, and city buses were running, free of charge.

On the Brooklyn Bridge, closed earlier because of high winds, joggers and bikers made their way across before sunrise. One cyclist carried a flashlight. Car traffic on the bridge was busy.

Bloomberg said it could be the weekend before the subway, which suffered the worst damage in its 108-year history, is running again. High water prevented inspectors from immediately assessing damage to key equipment.

The chairman of the state agency that runs the subway, Joseph Lhota, said service might have to resume piecemeal, and experts said the cost of the repairs could be staggering.

Power company Consolidated Edison said it could also be the weekend before power is restored to Manhattan and Brooklyn, perhaps longer for other New York boroughs and the New York suburbs.

The recovery and rebuilding will take far longer.

When Christie stopped in Belmar, N.J., during a tour of the devastation, one woman wept, and 42-year-old Walter Patrickis told him, "Governor, I lost everything."

Christie, who called the shore damage "unthinkable," said a full recovery would take months, at least, and it would probably be a week or more before power is restored to everyone who lost it.

"Now we've got a big task ahead of us that we have to do together. This is the kind of thing New Jerseyans are built for," he said.

Amtrak laid out plans to resume runs in the Northeast on Wednesday, with modified service between Newark, N.J., and points south. But flooding continued to prevent service to and from New York's Penn Station. Amtrak said the water in train tunnels under the Hudson and East rivers was unprecedented.

There was no Northeast Regional service between New York and Boston and no Acela Express service for the entire length of the Northeast Corridor. No date was set for when it might resume.

In Connecticut, some residents of Fairfield returned home in kayaks and canoes to inspect widespread damage left by retreating floodwaters that kept other homeowners at bay.

"The uncertainty is the worst," said Jessica Levitt, who was told it could be a week before she can enter her house. "Even if we had damage, you just want to be able to do something. We can't even get started."

The storm caused irreparable damage to homes in East Haven, Milford and other shore towns. Still, many were grateful the storm did not deliver a bigger blow, considering the havoc wrought in New York City and New Jersey.

"I feel like we are blessed," said Bertha Weismann, whose garage was flooded in Bridgeport. "It could have been worse."

And in New York, residents of the flooded beachfront neighborhood of Breezy Point in returned home to find fire had taken everything the water had not. A huge blaze destroyed perhaps 100 homes in the close-knit community where many had stayed behind despite being told to evacuate.

John Frawley acknowledged the mistake. Frawley, who lived about five houses from the fire's edge, said he spent the night terrified "not knowing if the fire was going to jump the boulevard and come up to my house."

"I stayed up all night," he said. "The screams. The fire. It was horrifying."

There were still only hints of the economic impact of the storm.

Forecasting firm IHS Global Insight predicted it would cause $20 billion in damage and $10 billion to $30 billion in lost business. Another firm, AIR Worldwide, estimated losses up to $15 billion.

"The biggest problem is not the first few days but the coming months," said Alan Rubin, an expert in natural disaster recovery.

Some of those who lost homes and businesses to Sandy were promising to return and rebuild, but many sounded chastened by their encounter with nature's fury. They included Tom Shalvey of Warwick, R.I., whose cottage on the beach in South Kingstown was washed away by raging surf, leaving a utility pipe as the only marker of where it once sat.

"We love the beach. We had many great times here," Shalvey said. "We will be back. But it will not be on the front row."